What is Fragile X syndrome?
Fragile X Syndrome is a genetic condition causing intellectual disability, behavioural and learning challenges and various physical characteristics. It is also the most common single gene cause of autism worldwide. It appears in people of all ethnic, racial and socio-economic backgrounds.
Though Fragile X syndrome occurs in both genders, males are generally affected with greater severity. Every week in Australia one child is born who is fully affected and 20 children are born who are carriers of Fragile X. It is estimated that 5 per cent of people with a diagnosis of an Autism Spectrum disorder also have Fragile X syndrome.
Although there is currently no cure, early intervention by health and educational professionals can assist people living with Fragile X to reach their full potential.
Fragile X Disorders – Don’t Miss Them. This article in the Australian Family Physician, the journal of the Royal Australian College of GPs is an excellent overview of Fragile X-associated disorders. (published July 2017)
Male carriers over the age of 50 have a 20-40% chance of developing Fragile X Tremor Ataxia syndrome (FXTAS). This is a neurological condition similar to Parkinson’s Disease, and may involve unsteadiness (ataxia), intention tremor (shaking) and memory problems.
Female carriers may also suffer from FXTAS, but is it less common.
Initial signs of the disorder may include difficulty writing, using utensils, pouring and walking. The symptoms progress over years or decades until many daily tasks become very difficult.
There may be a short term memory loss, anxiety, decreased sensation to touch in the lower extremities and rigidity in movement.
It is common to find these carriers mis-diagnosed as having Parkinsons disease, senile dementia or Alzheimers disease. More information on FXTAS on the NFXF site.
Female carriers may suffer from Fragile X Associated Primary Ovarian Insufficiency (FXPOI), a problem which can lead to infertility and early menopause in some female premutation carriers.
Primary Ovarian Insufficiency (POI) is a condition in which the ovaries stop functioning normally in a woman younger than age 40. Common symptoms of POI include absent or irregular periods and infertility.
POI is not menopause, even though women with POI may develop symptoms similar to those of menopause, such as hot flushes and vaginal dryness. POI differs from menopause in some important ways:
- Women with POI can still get pregnant in some cases because their ovaries may function irregularly to release viable eggs where as women who have completed menopause can not fall pregnant because their ovaries no longer release eggs.
- Women with POI can experience a return of/or irregular periods, however, women who have completed menopause will not have menstrual periods again.
Studies show that women who have POI of unknown cause have a 1/50 chance of being a carrier of Fragile X therefore the testing of women experiencing either POI or early menopause like symptoms is recommended.
Studies show that approximately 1 in 4 women carriers experience FXPOI and another 1 in 4 experience early menopause. It is thought that all women with Fragile X premutation status have some decrease in ovarian function. However many women with the Fragile X premutation are able to conceive and family planning options are recommended.
For more information:
- The Link Between Fragile X and POI (video)
- Women’s Health and The Fragile X Premutation (online publication)
- When to Consider Fragile X (online article from Medical Observer)
- National Fragile X Foundation website .